1. Field of the Invention
The present invention relates to a carbon dioxide (CO2) absorbent for exhaust gas and a method of preparing the same, and more particularly, to a CO2 absorbent for exhaust gas capable of being repeatedly used in capture of CO2 and recycling and a method of preparing the same.
2. Discussion of Related Art
Carbon dioxide (CO2) is one of the critical substances causing a greenhouse effect, and is known to have a potential to contribute to global warming since the emission of CO2 increases according to a continuous increase in use of fossil fuels.
Therefore, if CO2 emission is not controlled, problems caused by global warming cannot be overcome. Various methods of removing CO2 from exhaust gas generated by combustion of fossil fuels include a variety of methods such as wet chemical absorption, adsorption, membrane separation, and cryogenic fractionation. However, these methods have problems of high capture cost or difficulty in application to electric power plants or large-scale industries.
An effective method of removing CO2 from exhaust gas is dry CO2 capture technology. This method is technology of using a solid instead of a liquid solvent used in wet chemical absorption as an absorbent. That is, in this technology, CO2 contained in exhaust gas is captured by carbonate or bicarbonate generated by an active component and CO2 in a solid absorbent in an absorption reactor through a chemical reaction, and the absorbent absorbing CO2 can be repeatedly used by being recycled by additional heat in a recycling reactor.
In dry recycling/absorption technology, materials are inexpensive, regenerative and repeatedly used. In addition, the dry recycling/absorption technology is a sustainably growing field compared with other technologies in terms of design flexibility, environment-friendly capability, low-energy recycling, high-efficiency CO2 absorption force (absorbing capability and reactivity), etc.
Conventional patents relating to such dry recyclable scrubbing technology include U.S. Pat. Nos. 7,314,847B1 and 6,908,497B1, Japanese Patent Application Publication No. 2007-090208A, and U.S. Patent Application Publication No. 20070072769A1.
The above-mentioned patents mainly relate to an absorbent prepared by adding an active component to a support or an active component itself, and thus are inappropriate to be applied to a process of capturing and sequestrating CO2 while a particle of a solid absorbent is continuously transported between absorption and recycling reactors.